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In this perspective, we outline that a space borne gravitational wave detector network combining LISA and Taiji can be used to measure the Hubble constant with an uncertainty less than 0.5% in ten years, compared with the network of the ground based gravitational wave detectors which can measure the Hubble constant within a 2% uncertainty in the next five years by the standard siren method. Taiji is a Chinese space borne gravitational wave detection mission planned for launch in the early 2030 s. The pilot satellite mission Taiji-1 has been launched in August 2019 to verify the feasibility of Taiji. The results of a few technologies tested on Taiji-1 are presented in this paper. Gravitational wave astronomy has opened the door to test general relativity and the effect of gravity in the Universe. The authors present the capabilities of an overlap between space gravitational wave detectors LISA and Taiji to constrain the Hubble constant to 0.5%, in 10 years, and what can be learned from the satellite pilot Taiji-1 launched in 2019.

The Chinese Hα Solar Explorer (CHASE) is designed to test a newly developed satellite platform and conduct solar observations. The scientific payload of the satellite is an Hα imaging spectrograph (HIS), which can, for the first time, acquire full-disk spectroscopic solar observations in the Hα waveband. This paper briefly introduces CHASE/HIS including its scientific objectives, technical parameters, scientific application system, etc. The CHASE mission is scheduled to launch in 2021. It will complement the observations by on-orbit solar spacecraft (such as SDO, IRIS, STEREO and PSP), as well as future solar missions of the Solar Orbiter and Advanced Space-based Solar Observatory (ASO-S).

SPIHT and NLS (Not List SPIHT) are efficient compression algorithms, but the algorithms application is limited by the shortcomings of the poor error resistance and slow compression speed in the aviation and other areas requiring high-speed compression. In this paper, the error resilience and the compression speed are improved. The remote sensing images are decomposed by Le Gall5/3 wavelet, and wavelet coefficients are indexed, scanned and allocated by the means of family blocks. The bit-plane importance is predicted by bitwise OR, so the N bit-planes can be encoded at the same time. Compared with the SPIHT algorithm, this modified algorithm is easy implemented by hardware, and the compression speed is improved. The PSNR of reconstructed images encoded by high-speed SPIHT is slightly lower than SPIHT at rate 1bpp, but the speed is 4.5–6 times faster than SPIHT encoding process. The algorithm meets the high speed and reliability requirements of aerial applications.

Today technology innovation and fashion innovation are shortening the product life cycle, and result in demand uncertainty in supply chain. Under the environment of contact manufacturing (CM), a supply chain flexibility model is presented to describe in the relationship among capacity, lead time and inventory and the effective way to deal with demand uncertainty and mitigate the inventory risk through capacity flexibility and lead time flexibility. Under the policy on Order-up-to Level, an optimal order level is obtained to improve supply chain performance though optimizing the supply chain cost.

This paper uses game theory to analyze the behavior of collaboration knowledge creation in a typical two-tier supply chain under centralized decision-making condition and decentralized decision-making condition. The main purpose of this paper is to discuss how to establish the optimizing coordination mechanism of collaboration knowledge creation in supply chain so as to increase the efficiency of the whole supply chain finally.

This paper mainly makes a brief analysis on the performance evaluation of the BTO supply chain based on the relevant theories and mature models, and meanwhile puts forward a new modeling approach named 3D evaluation model based on customer service-oriented. The 3D model can provide a clear vision to the enterprises in the supply chain in order to operate in a right direction, pay attention to the key aspects that are selected, and also show the result of the evaluation directly under the accurate database, which may be the support to the decision-making for better development and related adjustment.

In view of the current stringent need to the real-time compression algorithm of the high-speed and high-resolution image, such as remote sensing or medical image and so on, in this paper, No List SPIHT (NLS) algorithm has been improved, and a fast parallel SPIHT algorithm is proposed, which is suitable to implement with FPGA. It can deal with all bit-planes simultaneously, and process in the speed of 4pixels/period, so the encoding time is only relative to the image resolution. The experimental results show that, the processing capacity can achieve 200MPixels/s, when the input clock is 50MHz, the system of this paper need 2.29ms to complete lossless compression of a 512×512×8bit image, and only requires 1.31ms in the optimal state. The improved algorithm keeps the high SNR unchanged, increases the speed greatly and reduces the size of the needed storage space. It can implement lossless or lossy compression, and the compression ratio can be controlled. It could be widely used in the field of the high-speed and high-resolution image compression.

This paper studies the comparison of the profit generated among supply chain before and after the VMI model being implemented and the logistics costs lying in the enterprise supply chain system and the relevant linkages by setting up a two-echelon supply chain model based on the EOQ (Economic Order Quantity) model under which the logistics costs are subdivided. In the paper, two functions are also set up, corporate profit function and logistics cost function, analyzing through which the improved performance of VMI implementation can be realized when the logistics costs decline. Thereby, the approach to raise the logistics management efficiency can be put forward through standardization corporate logistics activities.